Automatic miter machine

ABSTRACT

An apparatus for mitering portions of a workpiece to create mitered corners. The apparatus includes a base assembly. An X-Y positioning table is coupled to the base assembly. Clamp assemblies are coupled to the top of the positioning table for holding portions of a workpiece in place on the positioning table. A sewing machine is coupled to the base assembly and is adapted to sew a series of stitches along a V-shaped path. A notching device is coupled to the base assembly downstream from the sewing machine and is adapted for removing a portion of a workpiece defined by the V-shaped stitching path.

BACKGROUND

The preferred method of producing pillow-top mattresses is to have a mitered seam at the corners. Unlike other methods that restrict the depth of the gusset, mitering will produce the deepest and smoothest corners with any given materials. Gusset mitering has traditionally been a manual operation which often is quite tedious. The manual mitering operation typically requires a two-step procedure including sewing a V-shaped profile and cutting away the outer portion with scissors. The process can be slow and can present ergonomic challenges for operators.

SUMMARY

This summary is provided to introduce a selection of concepts in a simplified form that are further described below in the Detailed Description. This summary is not intended to identify key features or essential features of the claimed subject matter, nor is it intended to be used as an aid in determining the scope of the claimed subject matter.

A first illustrative embodiment of the present invention relates to an apparatus for mitering portions of a workpiece to create mitered corners. The apparatus has a base assembly and an X-Y positioning table coupled to the base assembly. At least two clamp assemblies are coupled to the top of the positioning table for holding portions of a workpiece in place. A sewing machine is also coupled to the base assembly and is positioned adjacent the positioning table. The sewing machine is used to sew a series of lock stitches along a V-shaped path. A notching device is positioned downstream from the sewing machine and is used to remove a triangular-shaped portion of the workpiece to create a mitered corner.

A second illustrative embodiment of the present invention relates to a machine for creating mitered corners of a pillow-top mattress gusset. The machine has a base and a work surface coupled to the base. At least two sewing clamps are disposed on the work surface and a sewing device is positioned adjacent the work surface. A cutting device, including a triangular shear, is located downstream from the sewing device. A disposal device is located adjacent the cutting device for removing cut portions of a workpiece from the cutting device. The machine also has at least one controlling computer for synchronizing the operation of the various components.

A third illustrative embodiment of the present invention relates to a multiple-stage system for automatically sewing and notching portions of a gusset to create a pillow-top mattress gusset having mitered corners. The system includes a clamping component disposed on an X-Y table, a sewing component for sewing a series of stitches along a V-shaped path, a notching component for removing a triangular-shaped portion of a gusset, and a controlling computer for automating a multiple-stage mitering process.

These and other aspects of the invention will become apparent to one of ordinary skill in the art upon a reading of the following description, drawings, and the claims.

BRIEF DESCRIPTION OF THE DRAWINGS

The present invention is described in detail below with reference to the attached drawing figures, wherein:

FIG. 1 is a perspective view of an apparatus for mitering portions of a workpiece in accordance with an embodiment of the present invention;

FIG. 2 is a front view of an apparatus for mitering portions of a workpiece in accordance with an embodiment of the present invention;

FIG. 3 is a side view of an apparatus for mitering portions of a workpiece in accordance with an embodiment of the present invention;

FIG. 4 is a partially cut away view of a clamp device holding a workpiece in place in accordance with an embodiment of the present invention;

FIG. 5 is a front view of an apparatus for mitering portions of a workpiece in accordance with an embodiment of the present invention;

FIG. 6A is a top plan view of an apparatus for mitering portions of a workpiece, wherein the work surface is shown in a first position corresponding to a production stage in accordance with an embodiment of the present invention;

FIG. 6B is a top plan view of the apparatus of FIG. 6A, wherein the work surface is shown in a second position corresponding to a production stage in accordance with an embodiment of the present invention; and

FIG. 6C is a top plan view of the apparatus of FIGS. 6A and 6B, wherein the work surface is shown in a third position corresponding to a production stage in accordance with an embodiment of the present invention.

DETAILED DESCRIPTION

Referring to the drawings, and particularly to FIG. 1, there is illustrated an exemplary apparatus 10 for mitering portions of a workpiece in accordance with an embodiment of the present invention. In an embodiment of the present invention, a workpiece may include a portion of fabric or webbing. In another embodiment, a workpiece may include a portion of folded gusset material such as, for example, gusset material that can be used in the construction of a pillow-top mattress. In a further embodiment, a workpiece may include a portion of folded gusset material with a flange piece attached thereto. In still further embodiments, a workpiece may include a portion of folded gusset material with a portion of border material attached thereto. It will be apparent to those skilled in the art that a workpiece, as used herein, may include any combination of the above, as well as any other type of workpiece that may be mitered.

The exemplary apparatus 10 illustrated in FIG. 1 includes a base assembly 12 which may, as shown in FIG. 1, include more than one base assembly portion 14,16. In other embodiments, the apparatus 10 may include only a single base assembly. As illustrated in FIG. 1, for example, the apparatus 10 illustrated includes two base assembly portions 14,16. The two base assembly portions 14,16 may be configured, as shown, to support different structures, and may be coupled to each other using any of various means known in the art. In an embodiment, one or more base assembly portions 14,16 may be fixably coupled by welding adjacent pieces thereof together. In another embodiment, the base assembly portions 14,16 may be rotatably coupled to each other, for example, to allow more convenient access to internal parts of the apparatus 10. In still further embodiments, the base assembly portions may not be coupled to each other at all.

As shown in FIG. 1, the first base assembly portion 14 includes a pair of rear legs 18 disposed on either side of the rear side of the first base assembly portion 14 and a pair of front legs 20 similarly disposed on either side of the front side of the first base assembly portion 14. In the illustrated embodiment, the two pairs of legs 18,20 are arranged in a standard rectangular design. In other embodiments, the legs may be arranged in various other designs such as for example, a triangular design. As will be appreciated by those skilled in the art, each of the base assembly portions 14,16 may have fewer than four legs, as the assembly portions may be coupled in such a manner as to provide adequate support with less than a full set of legs attached to each assembly portion. In other embodiments, each assembly portion may include any number of legs, arranged in any number of designs. It will be appreciated by those skilled in the art that the particular design and construction of the base assembly of a mitering apparatus is inconsequential so long as the base assembly provides appropriate support for the other elements.

The first base assembly portion 14, as shown in FIGS. 1-3, also includes two parallel horizontal support members 22 disposed between each of the rear legs 18 and two parallel horizontal support members 24 disposed between each of the front legs 20. The first base assembly portion 14 also includes two opposing pairs of parallel horizontal support members 26, each pair disposed between a rear leg 18 and an adjacent front leg 20. The first base assembly portion 14 further includes a platform 28, as shown in FIG. 2, which is disposed above the topmost support members 22 and 26. In an embodiment, the platform 28 may be attached to the support members 22, 26. In other embodiments, the platform 28 may be attached to other portions of the base assembly portion 14 such as, for example, the upper portions of the legs 18,20.

In further embodiments, the platform 28 may be rotatably coupled to the base assembly portion 14 in any manner known in the art. In still further embodiments, the base assembly portion 14 may not include platform 28, in which case further components may be coupled directly or indirectly using other means to the base assembly 12. In various embodiments, any number of various arrangements of support members or other construction elements may be implemented, and are intended to be within the ambit of the present invention.

As shown in FIGS. 1-3, the base assembly 12 may include a second base assembly portion 16. The base assembly portion 16 includes a pair of rear legs 30 and a pair of opposing front legs 32 with a pair of opposing horizontal cross-members 34, each cross-member 34 disposed between a rear leg 30 and an adjacent front leg 32. The base assembly portion 16 also includes a pair of opposing horizontal support members 36, which may support one or more structures, objects, or assemblies. It will be readily appreciated by those skilled in the art that the description of the base assembly herein and as illustrated in FIG. 1 is but one embodiment of a multitude of other possible configurations, and further that the particular construction and arrangement of the base assembly is not intended to be limited by the discussions and drawings herein. Any suitable configuration of a base assembly may be used as long as it provides adequate support for the other elements of the mitering apparatus.

With continued reference to FIGS. 1-3, the apparatus 10 includes an X-Y positioning table 40 coupled to the base assembly 12. While the designation of directions X and Y is entirely arbitrary, for the clarity of this description, the direction that runs parallel to the front edge of the apparatus 10 will be referred to as the X-direction herein, and the direction that runs perpendicular thereto (i.e., parallel to the side of the apparatus) will be referred to as the Y-direction. As illustrated in FIGS. 1-3, the X-Y positioning table 40 includes a work surface 41 moveably coupled to a pair of parallel rails 42 arranged along the X-direction and a pair of parallel rails 44 that are arranged along the Y-direction. The configuration of rails 42,44 and the moveable coupling between them and the work surface 41 allow for an X-Y positioning table 30 that can be moved in either the X-direction or the Y-direction, or in both directions. It will be appreciated to those skilled in the art that such an X-Y positioning table may be configured in any number of ways.

In an embodiment of the present invention, the X-Y positioning table 40 is configured so that the movement of the surface in either of the directions is achieved manually. In other embodiments such as, for example, the embodiment illustrated in FIGS. 1-3, the X-Y positioning table 40 may be configured so that its movement is automatic. In an embodiment, automated movement of the work surface 41 is achieved by an electric motor 46 which drives a series of belts (not shown) disposed within the rails 42,44. It will be appreciated by those skilled in the art that the operation of the X-Y positioning table 40 may be automated by any number of other drive systems, as well.

As shown in FIGS. 1 and 2, the apparatus 10 includes four clamp assemblies 48 coupled to the top of the positioning table 40. In an embodiment, the clamp assemblies 48 are fixably attached to the work surface 41 of the positioning table 40. In other embodiments, the clamp assemblies may be attached in another manner so that they can be rotated, shifted, or moved in some other fashion. The clamp assemblies 48 may be used for holding portions of a workpiece in place on the work surface 41 of the positioning table 40.

Turning to FIG. 4, an exemplary clamp assembly 48 is illustrated holding a portion of folded gusset material 51 in place. The clamp assembly 48 includes a top plate 52 disposed above a base plate 54. In an embodiment, the base plate 54 may be part of the work surface of the X-Y positioning table. In another embodiment, the base plate 54 may be a separate plate attached to the work surface. In an embodiment, the top plate 52 includes a V-shaped rear edge 55 that provides a guide for a sewing head. In another embodiment, as shown in FIG. 4, the base plate 54 also includes such a V-shaped rear edge 56. A lever 50 is rotatably coupled to the top plate 52 and is configured such that the clamping operation is achieved by manually applying a downward force to the lever 50, thus securing the folded gusset material 51 between the top plate 52 and the base plate 54. In other embodiments, the clamp assembly may be operated automatically such as, for example, by activating a motor or other system that operates the clamp.

In an embodiment, as illustrated in FIGS. 1-3, the mitering apparatus 10 includes four clamp assemblies 48. As will be appreciated by those skilled in the art, any number of clamp assemblies 48 may be attached to the work surface 41 of the positioning table 40. For example, as shown in FIG. 5, a mitering apparatus 11 is shown having two clamp assemblies 45 attached to the work surface 43. It should be understood that a workpiece may include extra material such as, for example borders or flanges, attached thereto. In this case, it may be desirable to provide the capability of positioning portions of the workpiece adjacent the clamp assembly. It should be evident from the configuration illustrated in FIG. 5 that the space between clamp assemblies 45 may be used in this manner. In other embodiments (not shown), a single clamp device may be attached to the positioning table. In still further embodiments, a plurality of clamp devices may be attached to the positioning table. The number of clamp devices used may depend upon the particular application for which the mitering apparatus is being used. In this regard, various embodiments of the invention may also include clamp devices that are removable, interchangeable, adjustable, and the like.

Returning to FIG. 1, the mitering apparatus 10 includes a sewing machine 58 which is coupled to the base assembly 12 and positioned adjacent the positioning table 40. In an embodiment, the sewing machine 58 is an industrial-type sewing machine such as, for example, the Model PLK-E0504, available from Mitsubishi Electric Automation, Inc. of Grapevine, Tex. The sewing machine 58, as illustrated in FIGS. 1 and 2, includes a sewing head 60 which is fed by a system of spools 62. The sewing machine 58 is operated by a motor 64, and is configured to sew a series of lock stitches along a V-shaped path defined by the V-shaped recessed section 56 of the clamp assembly 48. In an embodiment, the sewing machine 58 may be configured instead to sew a series of chain stitches, and in a further embodiment, the sewing machine 58 may be configured to sew a combination of lock stitches and chain stitches. The thread used by the sewing machine 58 and fed by the system of spools 62 may include any type of thread useful for creating stitches in a workpiece. In one embodiment, for example, the thread may comprise a Kevlar thread, which is useful for creating secure stitches while maintaining fire-proof qualities.

With continued reference to FIGS. 1 and 2, the mitering apparatus 10 further includes a notching device 70 coupled to the base assembly 12 and positioned next to the sewing machine 58. The notching device 70 is a cutting device that includes a triangular shear 72 for cutting a triangular-shaped portion out of a workpiece such as the folded gusset material 51. In an embodiment, the triangular-shaped portion removed from the workpiece includes a portion of the workpiece adjacent the V-shaped profile of stitches created by the sewing machine 58. The triangular shear 72 is configured to move in a downward motion through the workpiece 51. In an embodiment, the triangular shear 72 is designed to fit within the V-shaped recessed section 56 of the clamp assembly 48.

As illustrated in FIG. 1, the mitering apparatus includes a disposal system 76 for removing the triangular-shaped portion of the workpiece 51 from the notching device 70. The disposal system 76 includes a hose 74 through which the removed portion of the workpiece 51 travels. The hose 74 is coupled to a vacuum pump 82 which is fixably attached to the lid 80 of a container 78. The vacuum pump 82 is configured to create sufficient negative pressure in the hose 74 such that a removed portion of the workpiece 51 is drawn from the notching device 70 through the hose 74 and deposited in the container 78. The container 78 may include any type of container suitable for storing removed portions of a workpiece 51. In the embodiment illustrated in FIG. 1, for example, the container 78 may include a cylindrical container made of a lightweight and durable material such as plastic or rubber. In other embodiments, the container may be designed in any manner suitable for use in implementing the present invention, as will be appreciated by those skilled in the art.

As illustrated in FIGS. 1 and 2, the mitering apparatus 10 may include a controlling computer 90 which is configured for synchronizing the operation of the positioning table 40, the sewing machine 58, and the notching device 70. The controlling computer 90 may include any type of computing device capable of executing computer-readable instructions. In an embodiment, the controlling computer 90 may include a computing device such as a fully-programmable personal computer (PC). In further embodiments, the controlling computer 90 may comprise a dedicated computing device specially configured for synchronizing the operation of the mitering apparatus 10. The computing device 90 may be coupled to a display device 92 which may display any number of various types of information related to the operations of the apparatus 10. In an embodiment, display device 92 is a touch screen device capable of receiving input from a user as well as displaying output to a user. In other embodiments, the display device 92 may be configured only for display and not include input capabilities.

As further illustrated in FIGS. 1 and 2, the mitering apparatus 10 includes a control panel 94. The control panel 94 may be configured to receive input from a user and may include any type of input device that is configured to receive input from a user. In one example, as shown in FIGS. 1 and 2, the control panel 94 includes an “ON” button 95 and an “OFF” button. In other embodiments, the control panel 94 may include one or more switches or other devices for receiving user input. The “ON” button 95 illustrated here is configured to receive user input, which constitutes applying pressure to the button 95. In response to user input received by the “ON” button 95, the operation of the mitering apparatus 10 may be initiated.

As illustrated in FIGS. 1 and 2, the mitering apparatus includes a set of foot pedals 98. These foot pedals 98 may be configured to provide any number of user inputs to the apparatus 10 such as for example, inputs to control the sewing machine 58, inputs to control the positioning table 40, and inputs to control the notching device 70. In further embodiments, the mitering apparatus may contain only one foot pedal. In other embodiments, the mitering apparatus may contain more than two foot pedals. In still further embodiments, the mitering apparatus may not include foot pedals.

Additionally, as shown in FIGS. 1 and 2, the mitering apparatus 10 includes a guard rail 100 traversing the perimeter of the apparatus 10 and coupled to the base assembly 12. The guard rail 100 may be configured to help keep users safe from injury such as, for example, by providing a perimeter around the apparatus 10. It will be appreciated by those skilled in the art, however, that various embodiments of the present invention may not include a guard rail. Various other embodiments may include other types of safety features such as automatic shut-off, wall-like barriers disposed between the machine and the user (e.g. safety glass), coverings over moving parts, and the like.

Turning now to FIGS. 6A-6C, an exemplary mitering apparatus 110 for automating a multiple-stage mitering process is shown. As illustrated in FIG. 6A, the first aspect of a stage of a mitering process performed within an implementation of the present invention is shown. A stage may include any number of various operations suitable for mitering portions of a workpiece. Additionally, a multi-stage process may include any number of stages. As illustrated herein, in one embodiment, the number of stages in the process corresponds to the number of clamp devices attached to the work surface. For example, an apparatus having four clamp devices may operate in a four-stage cycle, whereas an apparatus having two clamp devices may operate in a two-stage cycle.

An exemplary mitering stage is illustrated in FIGS. 6A-6C. As shown in FIG. 6A, a first clamp device 112 is positioned adjacent to a sewing component 114 (e.g. sewing machine) such that the sewing component 114 is able to sew a series of stitches in a first secured portion of a workpiece along a V-shaped path defined by the V-shaped profile of the clamp device 112. In an embodiment of the present invention, the V-shaped path is accomplished by first positioning a leading edge of the first clamp device 112 adjacent to the sewing component 114. In an embodiment, the sewing component first sews a back tack, and proceeds to sew a series of stitches along the inside edge of the V-shaped profile of the first clamp device 112 as the positioning table 120 moves diagonally in the direction of the sewing component 114 and a notching component 116, thus causing the needle of the sewing component 114 to trace the inside leading edge of the profile of the first clamp device 112. Then, the positioning table moves diagonally away from the sewing component so as to allow the needle to trace the inside trailing edge of the profile of the first clamp device 112.

As illustrated in FIG. 4B, once the series of stitches is sewn into the secured portion of the workpiece, the first clamp device 112 is repositioned adjacent to the notching component 116. As shown in FIG. 4B, simultaneous to repositioning the first clamp device 112 adjacent to the notching component 116, a second clamp device 118 is positioned adjacent to the sewing component 114. The sewing process is repeated, with the sewing component 114 sewing a series of stitches along the inside leading edge of the second clamp device 118. When the positioning table 120 reaches a position, as illustrated in FIG. 4C, where the second clamp device 118 is positioned such that the needle of the sewing component 114 is positioned at the vertex 121 of the V-shaped profile of the second clamp device 118, the first clamp device 112 is positioned directly adjacent the notching component 116.

In the embodiment illustrated in FIGS. 4A-4C, when the positioning table is in the position illustrated in FIG. 4C, the notching component 116 cuts and removes a triangular-shaped portion from a portion of the workpiece, where the shape of the portion is defined by the V-shaped profile of the series of stitches. In an embodiment, the sewing component 114 briefly pauses in operation to allow the notching component 116 to complete its operation before the sewing component 114 begins to sew a series of stitches along the trailing edge of the second clamp device 118. Once the sewing component 114 has completed the V-shaped series of stitches, the stage is completed. In various embodiments of the present invention, a stage may be automatically or manually repeated until each of the desired miters is created.

Further embodiments of the present invention are directed toward an apparatus for mitering portions of a workpiece such as a pillow-top mattress gusset, the apparatus being configured to be coupled with other components of a pillow-top mattress assembly line. Additionally, further embodiments of the present invention relate to an apparatus for mitering portions of a workpiece wherein the work surface is stationary and the sewing head and notching device are coupled to an X-Y positioning table in such a manner as to provide for a multi-stage mitering functionality similar to that described above.

The present invention has been described in relation to particular embodiments, which are intended in all respects to be illustrative rather than restrictive. Alternative embodiments will become apparent to those of ordinary skill in the art to which the present invention pertains without departing from its scope.

From the foregoing, it will be seen that this invention is one well adapted to attain all the ends and objects set forth above, together with other advantages which are obvious and inherent to the system and method. It will be understood that certain features and subcombinations are of utility and may be employed without reference to other features and subcombinations. This is contemplated by and is within the scope of the claims. 

1. An apparatus for mitering portions of a workpiece to create mitered corners, the apparatus comprising: a base assembly; an X-Y positioning table coupled to the base assembly; at least two clamp assemblies coupled to the top of the positioning table for holding portions of a workpiece in place on the positioning table; a sewing machine coupled to the base assembly and positioned adjacent the positioning table, the sewing machine being adapted to sew a series of lock stitches along a V-shaped path at the desired location of the miter in the workpiece; and a notching device positioned downstream from the sewing machine for removing a triangular-shaped portion of a workpiece, defined by the V-shaped stitching path, to create a mitered corner.
 2. The apparatus of claim 1, wherein the workpiece comprises a portion of folded gusset material.
 3. The apparatus of claim 2, wherein the workpiece further comprises a portion of a flange piece secured to the portion of folded gusset material.
 4. The apparatus of claim 3, wherein the workpiece further comprises a portion of a border material attached to the portion of folded gusset material.
 5. The apparatus of claim 1, wherein the sewing machine is further adapted to sew a back tack at the beginning of the V-shaped path.
 6. The apparatus of claim 1, further comprising a disposal device for removing the triangular-shaped portion of the workpiece from the notching device.
 7. The apparatus of claim 1, further comprising a controlling computer for synchronizing operation of the positioning table, the sewing device, and the notching device.
 8. The apparatus of claim 1, wherein the clamp assemblies are adjustable for accommodating materials of differing thicknesses.
 9. The apparatus of claim 7, wherein the operation of the positioning table is achieved by using an electric motor coupled to the positioning table, the electric motor being adapted to cause the positioning table to move along a programmed operation path.
 10. The apparatus of claim 7, wherein the controlling computer receives user input from at least one foot pedal.
 11. A machine for creating mitered corners of a pillow-top mattress gusset, the machine comprising: a base; a work surface coupled to the base, the surface having at least two sewing clamps disposed thereon, wherein the work surface is operable to be moved in each of two perpendicular directions, and wherein each of the sewing clamps has a V-shaped profile; a sewing device positioned adjacent the work surface, the sewing device having a controlling computer, wherein the sewing device is programmed to create a series of stitches along an outside edge of the V-shaped profile of each of the sewing clamps; a cutting device comprising a triangular shear for cutting a triangular-shaped portion out of a gusset assembly piece, the cutting device positioned downstream from the sewing device such that the shear is operable to remove the portion adjacent the sewn, V-shaped profile; a disposal device for removing the triangular-shaped portion of the gusset assembly piece from the cutting device; and at least one controlling computer for synchronizing operation of the work surface, the sewing device, the cutting device, and the disposal device.
 12. The machine of claim 11, wherein the disposal device comprises a vacuum system having a hose coupled to a lower portion of the cutting device at one end and a disposal container at the other end.
 13. The machine of claim 11, wherein synchronizing operation comprises automating a multi-stage process.
 14. The machine of claim 13, wherein the multi-stage process comprises at least two stages.
 15. The machine of claim 14, wherein the multi-stage process comprises four stages.
 16. A multiple-stage system for automatically sewing and notching portions of a gusset to create a pillow-top mattress gusset having mitered corners, the system comprising: a clamping component disposed on an X-Y table, wherein the clamping component comprises at least two clamp devices, each clamp device having a V-shaped profile; a sewing component for sewing a series of stitches along the V-shaped profile of each of the clamp devices; a notching component for removing a triangular-shaped portion of a gusset; and a controlling computer for automating a multiple-stage mitering process, wherein a stage comprises: positioning a clamp device adjacent to the sewing component, wherein a portion of a gusset is secured by the clamp device; sewing a series of stitches in the secured portion of the gusset along a V-shaped path; repositioning the clamp device adjacent to the notching component; cutting a triangular-shaped portion from the secured portion of the gusset, wherein the series of stitches remains intact; and removing the triangular-shaped portion from the secured portion of the gusset.
 17. The system of claim 16, wherein sewing a series of stitches in the secured portion of the gusset comprises first sewing a back tack stitch in the first portion of the V-shaped path.
 18. The system of claim 16, wherein repositioning the clamp device adjacent to the notching component further comprises positioning a second clamp device adjacent to the sewing component.
 19. The system of claim 18, further comprising sewing a series of stitches in a second secured portion of the gusset along a V-shaped path defined by the V-shaped profile of the second clamp device.
 20. The system of claim 19, wherein a stage further comprises sewing a series of stitches in a second secured portion of the gusset simultaneous to cutting a triangular-shaped portion from a first secured portion of the gusset. 